How to Plan a Year-End Roth Conversion Strategy to Minimize Taxes Before December 31

A Roth conversion can reduce the amount of retirement savings you’ll eventually have to withdraw from a traditional IRA, but there’s a cost to making that move. The IRS generally adds the amount you convert to your taxable income for the year, so a poorly timed conversion can leave you with a larger tax bill than expected. Before December 31, you have an opportunity to review your 2026 income, calculate how much you can convert, and decide whether paying taxes now makes sense for your retirement plans.

Should You Do a Roth Conversion Before December 31?

A Roth conversion moves eligible funds from a traditional IRA or an eligible employer retirement plan into a Roth account. The taxable portion is generally added to your income for the year you complete the conversion. In return, the money can grow in the Roth account, and qualified withdrawals can be tax-free. Unlike a traditional IRA, a Roth IRA owned by the original account holder is not subject to lifetime RMDs.

Whether a conversion makes sense depends largely on your tax situation today and what you expect it to look like in retirement. If your income is temporarily lower, you have room in your current tax bracket, or you expect larger taxable withdrawals later, converting some money now may be worth considering.

How Much Room Do You Have in Your Tax Bracket?

Start with your estimated taxable income for 2026, then compare it with the upper limit of the federal tax bracket that applies to your filing status. The difference gives you an initial estimate of how much additional taxable income you can add before reaching the next bracket.

Example: Suppose you are a single filer with estimated 2026 taxable income of $180,000. The 24% federal tax bracket extends to $201,775 for single filers in 2026. That leaves $21,775 of room before reaching the 32% bracket.

If you convert $15,000 and the entire amount is taxable, your taxable income would rise to $195,000. The conversion would remain within the 24% bracket, assuming your other income and deductions do not change. At that marginal rate, the additional federal income tax attributable to the conversion would be approximately $3,600.

This is an example, not a recommended conversion amount. Your actual tax bill depends on your full tax return, including deductions, other income, and any applicable state taxes. If the conversion crosses into a higher bracket, only the portion falling within that bracket is generally taxed at the higher rate.

What Else Should You Consider?

Your federal tax bracket is only part of the decision. A conversion can also increase your income for calculations that affect certain deductions, credits, or other income-based costs.

If you are enrolled in Medicare or approaching eligibility, check whether the additional income could increase your Part B and Part D premiums through IRMAA. Medicare generally uses tax information from two years earlier, so a conversion completed in 2026 could affect your premiums in 2028.

You should also consider whether you can comfortably pay the conversion tax from money outside your retirement account. If doing so would leave you short on cash for living expenses, converting a smaller amount or waiting may be more appropriate.

A Roth conversion is worth considering when the tax you pay now fits your broader retirement plan.

A Step-by-Step Year-End Roth Conversion Strategy

Before choosing a conversion amount, walk through these eight steps. They will help you estimate the tax, decide how much to convert, and complete the transaction before December 31, 2026.

Step 1: Estimate Your Total 2026 Income

Start by adding up the income you have already received and what you expect to earn before December 31. Your estimate should include:

• Wages, bonuses, and self-employment income
• Pension income and taxable retirement distributions
• Interest, dividends, and capital gains
• Rental income and other taxable income

Pay attention to income that may arrive late in the year. A year-end bonus, sale of investments, or additional retirement distribution could change how much room you have in your current tax bracket.

If you are self-employed, use a realistic estimate of your remaining business income and deductible expenses. You do not need an exact figure yet, but your estimate should be close enough to help you decide how much additional taxable income you can accommodate.

Step 2: Review Your Current Tax Bracket

Once you have estimated your income, check the federal tax bracket that applies to your filing status. Use your estimated taxable income, not simply your gross salary, when reviewing the bracket limits.

Your marginal tax rate is the rate that generally applies to your next dollar of taxable income. If a conversion takes you into a higher bracket, only the portion that falls into that bracket is generally taxed at the higher rate. Your entire income does not suddenly become subject to that percentage.

Step 3: Estimate the Taxable Amount of the Proposed Conversion

Before calculating the tax, establish how much of the conversion will actually be taxable. For many people converting pre-tax traditional IRA funds, most or all of the converted amount is taxable. However, after-tax contributions, existing IRA basis, and the type of retirement account can change the result.

Check these points before moving the money:

• Traditional IRA contributions: Determine whether you have any after-tax basis from nondeductible contributions.
• Other IRA balances: Traditional, SEP, and SIMPLE IRA balances may affect the calculation under the IRS pro-rata rule. You generally cannot choose to convert only your after-tax money while ignoring other pre-tax IRA funds.
• Employer retirement plans: If you are moving money from a 401(k) or another workplace plan, confirm that the plan permits the transaction and how the funds will be treated for tax purposes.

Once you have established the likely taxable amount, use that figure to estimate the tax. The amount transferred into the Roth account and the amount included in taxable income are not always the same.

Step 4: Determine How Much Additional Taxable Income You Can Accommodate

Suppose your estimated taxable income is $190,000 and the applicable bracket ends at $201,775. You have $11,775 of room before reaching the next bracket.

You could compare these conversion amounts:

• $5,000
• $10,000
• Around $11,000

Calculate the additional tax for each option rather than automatically converting the full $11,775. Other income received later in the year, deductions, and state taxes could change the final result.

It is also worth comparing three broader scenarios: no conversion, a smaller partial conversion, and a larger conversion that uses most of your available bracket space. This gives you a clearer picture of what each option could cost.

Step 5: Check for Other Tax Consequences

Your federal tax bracket does not tell you the full cost of a Roth conversion. Before settling on an amount, check whether state taxes, changes to tax credits or deductions, or other income-based calculations could increase the overall cost.

If you must take an RMD for 2026, you generally need to take it before converting eligible remaining funds. An RMD itself cannot be converted to a Roth IRA.

These checks matter most when your income is close to a tax or benefit threshold. A conversion that fits within your federal tax bracket could still have a higher overall cost once you account for the other consequences.

Step 6: Decide Whether a Partial Conversion Makes Sense

You do not have to convert your entire traditional IRA balance in one year. A partial conversion lets you move an amount that fits your current tax situation while leaving the rest in the traditional account.

Compare a full conversion with one or more partial conversion amounts. Look at the additional tax each option would create, how much cash you would need to pay it, and how much would remain in your traditional IRA. This can help you decide whether converting a smaller amount now makes more sense than moving a larger balance in one year.

Step 7: Complete the Conversion Before December 31, 2026

If you want a Roth conversion to count toward your 2026 taxable income, the transaction generally needs to be completed by December 31, 2026. Submitting a request on the final day does not guarantee it will be processed in time.

Before initiating the conversion:

1. Contact your financial institution and confirm its year-end processing deadline.
2. Check whether investments need to be sold before the funds can be transferred.
3. Complete any required forms or account instructions.

4. Allow time for processing and resolve any delays before the deadline.

   Once the conversion is complete, save the transaction confirmation showing the amount and completion date. You will need these records when preparing your tax return.

Step 8: Plan for the Resulting Tax Liability

Before authorizing the conversion, estimate how much additional federal and state tax you may owe. Compare that amount with your available cash, current tax withholding, and estimated tax payments.

If your existing payments will not cover the additional liability, you may need to adjust your withholding or make an estimated tax payment. The appropriate approach depends on your income and payment history, so check the applicable IRS rules before making changes.

Whenever possible, plan to pay the tax with money outside your retirement account. Withdrawing funds from the account to cover the tax reduces the amount left invested. If you are younger than 59½, the amount used to pay the tax may also be subject to an additional tax on early distributions unless an exception applies.

When Does a Partial Roth Conversion Make Sense?

A partial Roth conversion can be useful when you want to move some retirement savings into a Roth account but do not want to recognize the tax on your entire balance in one year. These are some situations where it deserves a closer look.

• You have a lower-income year. You may have retired, reduced your working hours, or experienced a temporary drop in income. This can leave more room in a lower tax bracket, making a partial conversion worth considering.
• You have room left in your current tax bracket. You can convert an amount that fits within that space rather than converting so much that a larger portion falls into the next bracket.
• You expect higher taxable income in retirement. Future RMDs, pension income, investment income, or changes in tax law could increase your tax burden. Converting some money now may help spread the tax cost across several years.
• You want to reduce future RMDs. A conversion reduces the amount remaining in your traditional IRA, which may lower future RMDs. The amount converted, however, adds to your taxable income for the year.
• Your retirement investments have fallen in value. A lower account value may allow you to convert more shares for the same taxable amount. This only helps if the conversion fits your tax plan and you can afford the resulting bill.
• You are planning what to leave your heirs. A Roth IRA may offer tax advantages for beneficiaries, although distribution rules still apply. A conversion may be worth considering if you do not need the funds for your own expenses and can pay the tax without putting your retirement finances under pressure.

A partial conversion is not automatically the right choice in any of these situations. If your current tax rate is already high, you need the money for living expenses, or you expect a lower tax rate later, waiting may be more suitable.

Tax Factors to Check Before Completing a Year-End Roth Conversion

Before you finalize the amount, review these seven areas. They help you estimate the overall cost rather than focusing only on the federal tax bracket.

1. Taxable portion of the conversion: Confirm how much of the amount you plan to convert will be taxable. After-tax IRA basis and other account balances can affect the calculation.
2. Total 2026 income: Include wages, bonuses, investment income, retirement distributions, and other income you expect before year-end.
3. Federal tax bracket: Calculate how much room remains in your current marginal bracket and whether the conversion will push some income into the next one.
4. State income tax: Include any state tax due on the conversion. The result depends on where you live and the rules that apply to you.
5. Medicare premiums and IRMAA: Check whether the added income could affect future Medicare Part B and Part D premiums. Medicare generally uses tax information from two years earlier, so a 2026 conversion could affect premiums in 2028.
6. Net Investment Income Tax: Although the conversion itself generally is not net investment income, the increase in modified adjusted gross income may affect the tax you owe on other investment income.

7. Required Minimum Distributions: If you must take an RMD for 2026, account for it before converting eligible remaining funds. You cannot convert the RMD itself to a Roth IRA.

   If any of these factors could have a substantial effect on your finances, run the numbers before making the transfer. A tax professional can help you compare scenarios when the calculation involves multiple retirement accounts or state tax considerations.

How to Pay the Taxes on a Roth Conversion

The most straightforward approach is usually to pay the tax with money outside your retirement account. That leaves the full converted amount invested in the Roth account, where it can grow without annual tax on investment earnings. Using retirement funds to cover the tax reduces the amount you keep invested and may trigger an additional tax if the withdrawal is subject to the early distribution rules.

Review your existing tax withholding and estimated payments before the conversion. If the additional income means you may owe more than you have paid during the year, you may need to increase withholding or make an estimated payment. The amount and timing depend on your tax situation, so check the applicable IRS requirements rather than waiting until you file your return to find out whether you owe a penalty.

Roth Conversion Mistakes to Avoid at Year-End

Even a well-planned conversion can become expensive if you overlook a detail. Watch for these mistakes before moving your money.

1. Converting too much without estimating the tax impact. Calculate the taxable amount and compare several conversion scenarios before choosing a figure.
2. Ignoring other income received during the year. A bonus, capital gain, or unexpected distribution can reduce the room available in your current tax bracket.
3. Waiting until the last minute. Your financial institution may need time to process the transaction. Confirm its deadline well before December 31.
4. Ignoring state taxes. Federal income tax may be only part of the bill. Include state tax when deciding how much to convert.
5. Overlooking other tax consequences. Additional income can affect deductions, credits, and other income-based calculations. Review these before settling on a conversion amount.
6. Assuming a Roth conversion can be reversed. Roth conversions made in 2018 or later generally cannot be recharacterized back into a traditional IRA. Review the tax implications before authorizing the transaction.
7. Using retirement funds to pay the tax without considering the consequences. This reduces the amount left invested and may create additional tax consequences, particularly if you are under age 59½.
8. Making the decision based only on your current tax bracket. Future RMDs, state taxes, and your need for accessible cash can change whether a conversion makes sense.

Year-End Roth Conversion Checklist

Before you convert, work through these four stages to see whether the move makes sense for your finances.

1. Know Where You Stand

• Add up your income for 2026, including any year-end bonuses or investment gains.
• Check your current tax bracket and how much room remains before the next one.
• Confirm how much of your traditional IRA balance would be taxable.

2. Compare Your Options

• Calculate the estimated tax on a smaller conversion and a larger one.
• Check whether state taxes, Medicare premiums, or other income-based costs could increase.
• Account for any RMD you must take before converting the remaining eligible funds.

3. Make Sure You Can Afford It

• Decide how much you can convert without creating a tax bill that strains your budget.
• Check whether your savings, withholding, or estimated tax payments can cover the additional tax.
• Consider whether converting in stages over several years would suit your retirement plans better.

4. Complete the Move

• Confirm your financial institution’s year-end processing deadline.
• Submit the conversion early enough for it to be completed by December 31, 2026.
• Save the transaction confirmation and keep it with your tax records.

Closing Thoughts

A year-end Roth conversion works best when you know how much taxable income you expect, how much additional tax you can afford, and what you want your retirement savings to look like in the future. Start by estimating your income and comparing a few conversion amounts instead of rushing to convert as much as possible. Check state taxes and RMD requirements before making the decision, then leave enough time to complete the transaction by December 31. If the numbers do not work for 2026, you can review the opportunity again next year.

Frequently Asked Questions